Thanks for the replies. I started Josie on Royal Canin Special 30 for "sensitive, fussy" dogs. I started mixing it 1/2 and 1/2 with her previous food and after two weeks she's on the Royal Canin straight. No vomiting (self-induced or otherwise) since we started the switch! I wonder if there is something in the food that settles her stomach enough that the Nutro doesn't bother it anymore. I hope that takes care of the problem!